D7: I wish to use CASINO remotely using a debugger with a GUI (such as Totalview). How do I deal with the unacceptably slow response time that I get when I forward the X display e.g. using ‘ssh -X‘?

Here is a recipe that I (MDT) got to work on my machines (at work and at home) in connection with the Cetus machine at Argonne.

(1) If you are trying to do this at home without a static IP address, then subscribe to a free dynamic DNS service like http://www.noip.com/ . You end up with a daemon permanently running on your home machine that sends your current IP address (whenever it changes) to Noip who keep it linked with a name like ‘mikes_house.no-ip.biz‘. Then you can do ‘ssh mikes_house.no-ip.biz‘ from anywhere and it supposedly will figure out the current correspinding IP address.

Also make sure you instruct your router to open the ssh port and to forward any ssh traffic to the machine you want (which you will have setup with a static IP like 192.168.0.42 or whatever on your internal network).

You might also need to tell your home machine to open the correct ports for VNC (with OpenSuse Linux there’s an option for this in Yast2).

(2) On Cetus, type:

vncserver -geometry 1920x1080

It will respond

New 'cetuslac1:2 (your_user_name)' desktop is cetuslac1:2

Keep a note of the ‘:2‘ – this is the port number that you will need (and this might be different every time you do this).

where all occurrences of :2 and 02 refer to the port number from step (2).

The Totalview user support guy told me to add

-encodings '"tight zlib copyrect hextile rre corre raw"'

to the list of arguments to ssh, but that either corrupted my display, or had no effect. I’m not sure what this is supposed to do (and can’t be bothered to look it up – feel free).

(4) You should then get a big window containing a desktop (which will either be a fully functioning clone of the desktop on your home machine, or a partially functioning black desktop where you can’t e.g. resize windows, depending on which machine you use. I don’t know how to fix the black case – nobody said this is easy!).

(5) Inside the desktop should be a terminal window with which you can issue commands on Cetus. On Cetus, you would then do

casinoarch bluegene-xlf-cobalt-parallel.cetus_totalview.arch

then, e.g.

runqmc -n 1 --ppn=2 -T 1h -s --user.shmemsize=1000 --debug

Totalview will then launch inside the virtual desktop, and when you press a button it should respond quickly, rather than taking half an hour over it, as would happen with ‘ssh -X‘.

Then, assuming you’ve studied the Totalview manual for several days, you ought to be able to debug CASINO. Various bizarre behaviours may be encountered if you try to do this, but it essentially works.

(6) Once you’ve finished with it, close the Totalview window, then issue the following command on Cetus:

vncserver -kill :2

where :2 is the port number from step (2).

Note finally that Totalview also produce a ‘Remote Display Client’ which will supposedly do all this quasi-automatically, and which you can download and install this on your personal machine. However, not even the Totalview user support guys can make it work with Cetus (and I did ask).